CA2282362C - Systeme et procede pour accroitre la perte au couplage du terminal dans un terminal mains libres - Google Patents

Systeme et procede pour accroitre la perte au couplage du terminal dans un terminal mains libres Download PDF

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Publication number
CA2282362C
CA2282362C CA002282362A CA2282362A CA2282362C CA 2282362 C CA2282362 C CA 2282362C CA 002282362 A CA002282362 A CA 002282362A CA 2282362 A CA2282362 A CA 2282362A CA 2282362 C CA2282362 C CA 2282362C
Authority
CA
Canada
Prior art keywords
channel
transmit
receive
variolosser
loss
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
CA002282362A
Other languages
English (en)
Other versions
CA2282362A1 (fr
Inventor
Christopher Michael Forrester
Paul Vincent Coverdale
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nortel Networks Ltd
Original Assignee
Nortel Networks Ltd
Nortel Networks Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nortel Networks Ltd, Nortel Networks Corp filed Critical Nortel Networks Ltd
Publication of CA2282362A1 publication Critical patent/CA2282362A1/fr
Application granted granted Critical
Publication of CA2282362C publication Critical patent/CA2282362C/fr
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M9/00—Arrangements for interconnection not involving centralised switching
    • H04M9/08—Two-way loud-speaking telephone systems with means for conditioning the signal, e.g. for suppressing echoes for one or both directions of traffic

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Telephone Function (AREA)
  • Bidirectional Digital Transmission (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

L'invention concerne un procédé qui permet d'accroître la perte au couplage du terminal dans un terminal mains libres numérique semi-duplex. Quand le canal de réception du terminal est actif, un code repos, qui effectivement est zéro, est émis par un générateur de code repos. Quand le code d'émission du terminal est actif, un signal vocal normal est émis. Pour déterminer quel canal est actif, un niveau de signal vocal de réception est mesuré au niveau de la sortie du canal de réception, et un signal d'émission "virtuel" est calculé à partir d'un signal dans le canal d'émission avant le générateur de codes repos.
CA002282362A 1997-03-06 1998-02-24 Systeme et procede pour accroitre la perte au couplage du terminal dans un terminal mains libres Expired - Fee Related CA2282362C (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US08/813,031 US5982755A (en) 1997-03-06 1997-03-06 System and method for providing high terminal coupling loss in a handsfree terminal
US08/813,031 1997-03-06
PCT/CA1998/000138 WO1998039905A2 (fr) 1997-03-06 1998-02-24 Systeme et procede pour accroitre la perte au couplage du terminal dans un terminal mains libres

Publications (2)

Publication Number Publication Date
CA2282362A1 CA2282362A1 (fr) 1998-09-11
CA2282362C true CA2282362C (fr) 2002-11-26

Family

ID=25211269

Family Applications (1)

Application Number Title Priority Date Filing Date
CA002282362A Expired - Fee Related CA2282362C (fr) 1997-03-06 1998-02-24 Systeme et procede pour accroitre la perte au couplage du terminal dans un terminal mains libres

Country Status (5)

Country Link
US (1) US5982755A (fr)
EP (1) EP0965219A2 (fr)
AU (1) AU6084198A (fr)
CA (1) CA2282362C (fr)
WO (1) WO1998039905A2 (fr)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6385176B1 (en) * 1998-06-04 2002-05-07 Lucent Technologies Inc. Communication system based on echo canceler tap profile
US6754337B2 (en) * 2002-01-25 2004-06-22 Acoustic Technologies, Inc. Telephone having four VAD circuits
US6904146B2 (en) * 2002-05-03 2005-06-07 Acoustic Technology, Inc. Full duplex echo cancelling circuit
JP2006108777A (ja) * 2004-09-30 2006-04-20 Toshiba Corp 電話端末及びこの電話端末を使用した電話システム、及び電話端末の制御方法
US7689233B2 (en) * 2005-12-30 2010-03-30 Vtech Telecommunications Limited Remote switching for handset handsfree speakerphone
KR100764788B1 (ko) * 2006-03-16 2007-10-11 엘지전자 주식회사 이동통신 단말기 및 이동통신 단말기의 음성신호 송신방법
US20080247535A1 (en) * 2007-04-09 2008-10-09 Microsoft Corporation Method and apparatus for mitigating impact of nonlinear effects on the quality of audio echo cancellation
US8514860B2 (en) * 2010-02-23 2013-08-20 Broadcom Corporation Systems and methods for implementing a high throughput mode for a MoCA device

Family Cites Families (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3973086A (en) * 1975-04-24 1976-08-03 Bell Telephone Laboratories, Incorporated Digital echo suppressor break-in circuitry
US4110560A (en) * 1977-11-23 1978-08-29 Gte Sylvania Incorporated Communication apparatus
US4165449A (en) * 1978-01-03 1979-08-21 Storage Technology Corporation Echo suppressor circuit
US4609788A (en) * 1983-03-01 1986-09-02 Racal Data Communications Inc. Digital voice transmission having improved echo suppression
US4652703A (en) * 1983-03-01 1987-03-24 Racal Data Communications Inc. Digital voice transmission having improved echo suppression
US5408466A (en) * 1984-12-06 1995-04-18 Motorola, Inc. Duplex interconnect dispatch trunked radio
US4979163A (en) * 1988-12-28 1990-12-18 At&T Bell Laboratories Echo suppression arrangement for an adaptive speakerphone
US5016271A (en) * 1989-05-30 1991-05-14 At&T Bell Laboratories Echo canceler-suppressor speakerphone
US5014294A (en) * 1990-02-01 1991-05-07 Motorola Inc. Speakerphone for cellular telephones with howl prevention, detection, elimination and determination
FR2665807B1 (fr) * 1990-08-08 1994-06-03 Alcatel Business Systems Appareil telephonique "main libre".
US5075687A (en) * 1990-09-27 1991-12-24 Advanced Micro Devices, Inc. Echo suppression with both digital and analog variable attenuators
US5212685A (en) * 1991-03-21 1993-05-18 International Business Machines Corporation Control circuit for half-duplex/simplex interface in communication system
GB2256351B (en) * 1991-05-25 1995-07-05 Motorola Inc Enhancement of echo return loss
US5548638A (en) * 1992-12-21 1996-08-20 Iwatsu Electric Co., Ltd. Audio teleconferencing apparatus
JPH06338934A (ja) * 1993-05-25 1994-12-06 Exar Corp 事象駆動型制御回路を有するスピーカーホーン
US5381475A (en) * 1993-12-02 1995-01-10 At&T Corp. Arrangement for suppressing echoes in a digital portable telephone
US5771440A (en) * 1996-05-31 1998-06-23 Motorola, Inc. Communication device with dynamic echo suppression and background noise estimation

Also Published As

Publication number Publication date
AU6084198A (en) 1998-09-22
CA2282362A1 (fr) 1998-09-11
WO1998039905A3 (fr) 1998-12-23
WO1998039905A2 (fr) 1998-09-11
EP0965219A2 (fr) 1999-12-22
US5982755A (en) 1999-11-09

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